EFFECTS OF VOLUNTARY TRAINING ON PANCREATIC ENZYME ACTIVITY AND ACINAR CELLS IN RATS

Abstract

The authors have found that compulsory training using treadmill running increases pancreatic weight, protein content, and enzyme activity in hypertrophied acinar cells in rats. The purpose of the present study was to investigate the effect of voluntary running exerise on the exocrine pancreas in rats. Female F344 rats were divided into control, compulsory training, and voluntary training groups. The compulsory trained rats were exercised for 60 min on a treadmill (final speed, 35 m/min), 5 days a week, for 8 weeks. The voluntary trained rats were exercised on a voluntary basis on a wheel ergometer with a load of 30% of their body weight every day. Mean running distance for the voluntary training group was 5.2±1.0 km/day. Final body weight for the compulsory and voluntary training groups was significantly lower than for the control group. Soleus muscle weight and citrate synthase activity of the plantaris muscle for the compulsory and voluntary training groups were significantly higher than for the control group. Pancreatic wet weight, protein content, and amylase and lipase activities for the compulsory and voluntary training groups were significantly higher than for the control group. Pancreatic wet weight, protein content, and amylase and lipase activities for the compulsory and voluntary training groups were significantly higher than for the control group. Total DNA content of whole pancreas in the voluntary training group was significantly higher than for the control and compulsory training groups. Electron micrographs revealed that acinar cells obviously hypertrophied and zymogen granules increased in the compulsory and voluntary training groups rats compared with the compulsory group. These results suggest that voluntary training increases pancreatic weight and protein content in hypertrophied and/or hyperplasic acinar cells, which in turn increases synthesis and the storage of exocrine pancreatic enzymes.